Oviposition and development in the glass frog Hyalinobatrachium orientale (Anura: Centrolenidae)

Abstract

Oviposition and development in the glass frog Hyalinobatrachium orientale (Anura: Centrolenidae). Oviposition and external embryonic developmental features are described in the Tobago glass frog, Hyalinobatrachium orientale. Egg clutches are nearly always laid on the undersides of leaves (one exception); usually leaves of Heliconia sp. are used, but Philodendron and palms may be used in the absence of Heliconia. Clutches contain 28.0 ± 5.3 eggs (mean ± SD) and eggs are 1.86 ± 0.11 mm in diameter. The behavior of one amplectant pair was followed for more than five hours; the pair rotated several times around a small area of the leaf depositing eggs in a tight spiral formation. External embryonic features were observed by scanning electron microscopy. Surface ciliation is extensive up to the time of hatching when it is lost; external gills are short and a cement gland is absent. Hatching gland cells were detectable on the anterodorsal surface of the head from Day 4 after deposition and persisted until at least Day 10, and hatching occurred between Days 9 and 16. During this period, progressive development in tail length, surface pigmentation, intestinal coiling, and oral disc features was observed. Post-hatching larvae reared for six weeks grew 37% in length and tripled in weight, but remained at Gosner Stage 25.Keywords: amphibians, embryonic development, glass frogs, oviposition, Tobago, West Indies.Resumo Ovipostura e desenvolvimento na perereca-de-vidro Hyalinobatrachium orientale (Anura: Centrolenidae). Descrevemos aqui características da ovipostura e do desenvolvimento embrionário externo da perereca-de-vidro de Tobago, Hyalinobatrachium orientale. Os ovos são quase sempre depositados na superfície abaxial das folhas (com uma exceção). Geralmente, são usadas folhas de Heliconia sp., mas, na ausência destas, podem ser usadas folhas de Philodendron sp. e de palmeiras. As desovas contêm 28,0 ± 5,3 ovos (média ± DP) e os ovos possuem diâmetro de 1,86 ± 0,11 mm. O comportamento de um casal em amplexo foi acompanhado por mais de cinco horas; o casal girou 4 Phyllomedusa -14(1), June 2015 diversas vezes em torno de uma pequena área da folha, depositando os ovos em uma formação espiral apertada. As características embrionárias externas foram observadas por microscopia electrônica de varredura. A ciliação é extensa até o momento da eclosão, quando é perdida; as brânquias externas são curtas, e não existe uma glândula de cemento. Células glandulares de eclosão foram detectadas na superfície anterodorsal da cabeça a partir do dia Dia 4 após a ovipostura e persistiram até pelo menos o Dia 10, e a eclosão ocorreu entre os Dias 9 e 16. Durante esse período, foi observado o desenvolvimento progressivo do comprimento da cauda, da pigmentação superficial, do enovelamento do intestino e das características do disco oral. Após a eclosão, larvas criadas por seis semanas cresceram 37% no comprimento e tiveram seu peso triplicado, mas permaneceram no estágio 25 de Gosner.Palavras-chave: anfíbios, desenvolvimento embrionár...

Patterns of parental care in Neotropical glassfrogs: fieldwork alters hypotheses of sex‐role evolution

“…For the 11 species monitored daily through development to calculate care duration (Table S3), we found the earliest hatching occurred at external gill resorption (onset of Gosner 1960 stages 24/25). This is consistent with published information from four additional species (Vockenhuber et al ., ; Delia et al ., ; Nokhbatolfoghahai et al ., ; Bravo Valencia & Delia, ). We considered the period to reach stage 24/25 as the obligate embryonic period to assess care durations relative to embryo development.…”

The Adhesive Glands during Embryogenesis in Some Species of Phyllomedusinae (Anura: Hylidae)

“…Whether adhesive glands are involved in this behavior remains unknown, and also, detailed observations of hatching embryos without adhesive glands are needed to compare hatching mechanisms and performances. Previous studies relate the absence of adhesive glands with a late hatching Nokhbatolfoghahai et al, 2015); however, observations in Phyllomedusinae show that this may not be the case, because embryos hatch late independently of the absence (e.g., P. boliviana) or presence (e.g., P. azurea) of adhesive glands. Furthermore, plastic hatching is independent from gland presence, because variations in the time of hatching are observed in embryos with (e.g., P. sauvagii) and without (e.g., P. trinitatis) adhesive glands.…”

Observations on metamorphosing tadpoles of Hyalinobatrachium orientale (Anura: Centrolenidae)

“…Our finding that metamorphs of Hyalinobatrachium orientale always perched on the upper sides of leaves suggests that this may be a strategy to avoid ground-dwelling predators. Mating adults and egg clutches always are found on the lower sides of leaves (Nokhbatolfoghahai et al 2015), but these leaves are over water. There are some 10 species of snakes on Tobago (Auguste 2018) that may prey on small frogs and most likely would approach from the ground.…”

“…The Tobago population of the glass frog Hyalinobatrachium orientale is distinct enough from the Venezuelan population to merit subspecies designation as tobagoense (Jowers et al 2014). Parental care (Lehtinen and Georgiadis 2012), development to hatching (Nokhbatolfoghahai et al 2015), early tadpole morphology (Downie et al 2015), and early tadpole behavior (Byrne et al 2018) have been described in Hyalinobatrachium orientale. Herein, we report observations on metamorphosing individuals found in the field.…”